A turbofan engine having one or more heat exchangers tied to a power gearbox is provided. The power gearbox mechanically couples a low pressure spool and a fan of the turbofan engine. The one or more heat exchangers have a heat exchanger capacity defined by a resultant heat transfer surface area density associated with the one or more heat exchangers multiplied by a heat conductance factor that relates a power gearbox heat load, a fan power consumption function, a fan diameter of the fan, and a bypass ratio of the turbofan engine. The heat exchanger capacity is between 0.77 and 48 for a rotational speed of the low pressure spool between 2,000 and 16,000 revolutions per minute at one hundred percent capacity and a resultant heat transfer surface area density being between 3,000 m.sup.2/m.sup.3 and 13,000 m.sup.2/m.sup.3.

This transition piece comprises a pair of side plates which face each other across an axis, a plate inside the curve which, with reference to the axis, is arranged inside the curve where the downstream portion curves relative to the upstream portion on the axis, and a plate outside the curve which, with reference to the axis, is arranged outside the curve on the side opposite of the aforementioned inside the curve. The plate inside the curve, the plate outside the curve and the pair of side plates each has multiple passage groups which are configured from multiple cooling passages that allow flow of a cooling medium and that extend in the axis direction and are arranged side-by-side in the circumferential direction, and one or more headers which allow flow of the cooling medium and which extend in the circumferential direction. The number of the one or more headers of the plate inside the curve is less than the number of the one or more headers in the plate outside the curve and the pair of side plats.

An apparatus and method for flowing cooling air through an outer wall of an engine component such as an airfoil. The airfoil having the outer wall can include a skin layer and a porous layer. The skin layer can include a skin cooling circuit for providing the cooling air from an interior of the airfoil to the exterior of the airfoil through the porous layer.

A turbine wheel for a gas turbine engine including a compressor impeller and a radial inflow turbine integral to or attached to the compressor impeller is provided. A compressor turbine wheel including features to increase surface area of a surface of the compressor impeller and/or the radial inflow turbine and/or a passage to flow air between the compressor impeller and the radial inflow turbine is further provided. Methods for cooling radial inflow turbines integral to compressor impellers are further provided.

The invention relates to a device (30) for cooling heat-sensitive control members (29) of a pneumatic or electropneumatic valve (20), comprising a containment casing (31) designed to contain said control members (29): a fresh air inlet (32) in said containment casing (31); an air outlet (33) of said containment casing, provided with a ventilation air tube (34) that comprises: an air acceleration column (35) which puts into fluidic communication said containment casing (31) and the air outlet (33); a primary supply (37) for supplying the acceleration column (35) with primary air; a secondary supply (38) for supplying the acceleration column (35) with secondary air, provided in said containment casing (31) such that the primary air can drive and accelerate the secondary air in the direction of the air outlet so as to produce forced air ventilation in said containment casing (31) between the air inlet (32) and the air outlet (33).

A turbine airfoil is provided with at least one insert positioned in a cavity in an airfoil interior. The insert extends along a span-wise extent of the turbine airfoil and includes first and second opposite faces. A first near-wall cooling channel is defined between the first face and a pressure sidewall of an airfoil outer wall. A second near-wall cooling channel is defined between the second face and a suction sidewall of the airfoil outer wall. The insert is configured to occupy an inactive volume in the airfoil interior so as to displace a coolant flow in the cavity toward the first and second near-wall cooling channels. A locating feature engages the insert with the outer wall for supporting the insert in position. The locating feature is configured to control flow of the coolant through the first or second near-wall cooling channel.

A coiling heat exchanger, characterized by a heat exchanger spiral consisting of a liquid shield with fins, whereby neighboring coils of the spiral of the liquid shield are spaced apart from one another by the fins and connected to one another in a heat exchanging manner and that the liquid shield is perfused by liquid, whereby gas flows between the neighboring coils of the spiral of the liquid shield along the coiling axis.

A gas turbine having a combustion chamber with exhaust section through which combustion gas is exhaustable, plenum chamber and compressor are provided. The plenum chamber is coupled to the compressor wherein a first quantity of compressed fluid is injectable therein at a radially inner wall of the plenum chamber. A guide vane section with at least one airfoil is coupled to the exhaust section so combustion gas is flowable against the airfoil. The exhaust section and guide vane section are housed inside the plenum chamber. The airfoil has a first flow chamber where a second quantity of compressed fluid is flowable through the guide vane section from the compressor in the direction from the inner wall to a outer wall of the plenum chamber before being discharged. The second quantity of compressed fluid streamable through the guide vane section is larger than the first quantity of the compressed fluid.

A combined fan for cooling a heat source includes a hub and multiple blades. The hub has a first side and a second side opposite to each other. The blades are distributed along an outer circumferential surface of the hub, and each of the blades includes a first part extending from the hub and a second part connected to the first part. Each of the second parts protrudes beyond the first side or the second side, and each of the second parts is formed by multiple strip structures. Therefore, each of the strip structures can be closer to a surface of the heat source to dissipate the heat more effectively.

A thermal management system for transferring heat between fluids includes a thermal transport bus through which a heat exchange fluid flows. Additionally, the system includes a heat source heat exchanger arranged along the bus such that heat is added to the fluid flowing through the heat source heat exchanger. Moreover, the system includes a plurality of heat sink heat exchangers arranged along the bus such that heat is removed from the fluid flowing through the plurality of heat sink heat exchangers. Furthermore, the system includes a bypass conduit fluidly coupled to the bus such that the bypass conduit allows the fluid to bypass one of the heat source heat exchanger or one of the heat sink heat exchangers. In addition, the system includes a valve configured to control a flow of the fluid through the bypass conduit based on a pressure of the fluid within the bus.